In the manufacture and assembly of levels of the type described above, it is critical that the liquid level indicators such as vials, spirit tubes, and bubble chambers of the levels are precisely aligned relative to a working surface to ensure functional and operating accuracy. In the past, it has been the practice to obtain this accuracy by providing a separate and independent liquid level indicator and subsequently positioning the liquid level indicator in a precise manner within the level. The liquid level indicator has typically been located in an aperture or bore in a housing member of the level utilizing precision equipment and highly skilled labor to assure accurate placement of the liquid level indicator with respect to the work surfaces of the level. Unfortunately, the use of highly skilled labor and the continuing requirement for meticulous alignment of the liquid level indicator contribute greatly to the cost of the end product.
Other attempts at cost reduction have been made in the molding and subsequent machining of the liquid level indicator. However, such operations involve not only the time and expense of skilled labor but are subject to machining error, thereby adding to the cost and possibility of error associated with their production.
Accordingly, it is the general aim of the invention to provide a new and improved line level in a manner as to effectively reduce the labor requirements necessary in its production without compromising its accuracy. It is also desirable to provide an easily assembled line level in a simple, economical manner while obviating the requirements for machining operations which increase the cost and are susceptible to introducing inaccuracies in the finished level.
It is further desirable to provide a new and improved line level in which a liquid level indicator may be precisely mounted without a need for special machinery. It is also within the purview of the invention to provide a liquid level indicator which can be automatically and consistently mounted in the proper position both radially and axially without special tools.